The cave is a network of sorts, connecting two large caves, Sac Actun, measuring 163 miles, and Dos Ojos, measuring 52 miles. The team who discovered the connection, Gran Acuĺfero Maya (GAM), have named them the Sac Actun cave system. One of the GAM's exploration directors, Robert Schmitter, has been exploring the maze-like caves, with their many-branched upper- and lower-level passages, for more than a decade. The organization itself is dedicated to the study and preservation of the waters underneath the Yucatan Peninsula.

The system is near Tulum, a beach resort in the state of Quintana Roo that was a walled city in the times of the Maya, one of Mexico's most well-known ancient societies. Maya thrived throughout Mexico and Central America from about 1800 B.C. to the 9th Century A.D.

In addition to the many-layered nature of the caves are flooded sinkholes called cenotes. Archaeologists have found Mayan relics in several cenotes. Found in one 2014 dig were human bones and religious objects, along with more traditionally found items like water pitchers, stone tools, and shells. Maya regarded cenotes as sacred places, perhaps even portals to the gods.

Sac Actun itself had been the world's second-longest underwater cave, slightly behind Ox Bel Ha, another Quintana Too cave, which measures 168 miles in length.

The GAM team is already at work trying to connect an 11-mile-long network of cenotes to the Sac Actun cave system; doing so would further establish the world record.